I have some cql attr > PLACEHOLDER that I want to convert to valid XML using geotools. I have heard of terms like filter functions that can somehow replace the placeholder with a function, but not totally sure the best way to go about this.

1 Answer 1


I wrote a blog post about this a few years ago.

    org.geotools.xml.Configuration configuration = new org.geotools.filter.v1_0.OGCConfiguration();
    org.geotools.xml.Encoder encoder = new org.geotools.xml.Encoder(

    line = "attr > PLACEHOLDER";
    try {
        Filter filter = CQL.toFilter(line);
        // System.out.println("\t" + filter);
        encoder.encode(filter, org.geotools.filter.v1_0.OGC.Filter, System.out);
    } catch (CQLException e) {

Obviously, in a real program, you'd want to write to a StringBuffer or something instead of stdout. If you want to use the filter at other points in the GeoTools code all you need is filter.

  • Thanks for this writeup, pretty cool stuff. Is there a possible implementation you know of regarding functions? I know this is valid in the 2.0 spec Feb 15, 2018 at 18:08
  • Just change the configuration to version 2.0
    – Ian Turton
    Feb 15, 2018 at 18:59
  • Ideally what I'm wanting is when a function tag is hit in the XML when I'm converting from XML to CQL it will replace all the placeholders with my input parameters. Feb 15, 2018 at 19:25

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